My daughter (4th grade) is comparing three types of bedding products for her guinea pigs to see which one rates the best overall in odor control, expense, ease of clean up, and happiness of Guinea pigs. We are having trouble designing the best way to measure these results and show the procedure steps. We want to show a graph at the end of the experiment that would show the results but need help designing the procedure steps.Thank you for your assistance.

Welcome to Science Buddies! This is a unique and original idea for a science project. However, as you realize, it is challenging to find a way to measure the parameters that make good guinea pig bedding. Here are my suggestions:

First, do as much background reading as possible on this subject. It is difficult to find sources from the scientific literature on this subject, but there are some sites that appear to be written by experienced guinea pig owners such as the following:

Your daughter should not include any type of bedding that is known to be toxic to guinea pigs such as sawdust or cedar shavings.

1. Cost: This is a straightforward parameter. A bar graph with the cost of each type of bedding would be a good way to compare the cost of each type of bedding.

2. Ease of clean-up. Your daughter could write a detailed protocol for cleaning a guinea pig cage. Then she could measure the time using a stopwatch required to clean a cage filled with each type of bedding. It would be best if she could do this part of the experiment in duplicate herself and have someone else time her, or, better, have 2 or 3 other people follow her directions while she times them. You could use clean bedding and reuse it multiple times. Be sure to keep the weight or volume or each type of bedding and all other parameters identical to make this a good test. Again, results could be shown using a bar graph.

3. Odor control: The characteristic odor from used pet bedding is due the formation of ammonia.

Here is a research paper that describes various methods of measuring the ammonia produced from animal bedding. Please notice the detail on the air sampling and the variety of techniques used to measure ammonia.

You should be able to obtain an test kit for ammonia from a local aquarium store or on-line. I recommend trying a kit to see if it will work with guinea pig bedding. Then for the analysis, your daughter could measure the ammonia produced over time for each type of bedding used with the same number of guinea pigs. Perhaps small samples of bedding could be taken every day and stored in sealed plastic bags in a freezer and tested all at together after the bedding has been changed. The results should be compared with the actual odor reported by various family members. You can use ammonia from the cleaning section of the grocery store as a positive control. Also, be sure to record the temperature to ensure that this parameter is controlled for this experiment.

Data that is collected over time can be presented in a line graph with time of the x-axis and ammonia concentration on the y-axis. The graph would include one line for the results of each type of bedding. If results are done in duplicate (best, but a lot of work), then use one color for each type of bedding.

Here is information for making graphs. If your daughter does not know how to use Excel, then have her make the graphs by hand.

4. Guinea pig happiness. Guinea pigs exhibit various behaviors when they are happy and unhappy, and there is a lot of individual variation so each type of bedding should be evaluated with the same animal or group of guinea pigs.

Your daughter could work with one or more guinea pigs and place them on new bedding and record behavior for a specific time (10-15 minutes?). Apparently popcorning indicates happiness and chirping suggests unhappiness. Can your daughter identify any other behaviors that reflect her pets' state of mind? For this part of the experiment, it will be important to make sure that all other parameters are controlled, such as handling, time of day, and temperature.

Another possibility, would be to place the guinea pig in a large cage with two types of bedding available and observe which side of the cage the animal chooses. Or, perhaps construct a maze with areas that include each type of bedding and record the time that the guinea pig spends on each type of bedding.

Be sure and do this test at least twice to make sure results are reproducible. Perhaps your daughter could devise a guinea pig happiness scale with a range of 1-10. This would give a number that could be shown in a bar graph.

Here is information for making graphs. If your daughter does not know how to use Excel, then have her make the graphs by hand.

Finally, since this is a project involving guinea pigs, you should review the information for doing projects with vertebrate animals. Talk to the teacher and get approval or find out if you need approval from your local scientific review committee. Since you will not be using anything that is toxic for guinea pigs, there should not be a problem in getting approval.